All of those issues that you’ve cited are also outcroppings of patriarchy, which is a dominance hierarchy. Women/girls live in patriarchal society also and are not immune from participating in some of it’s worst elements or from trying to climb the pyramid by stepping over top of others. They are simply emulating the behaviors of their male peers. It’s considered desirable to be tough, strong, badass, in control (masculine qualities) but not to have traditional feminine qualities. Those are for fags and sissies…. and girls. The fact that some of these people are actually female is irrelevant. If the society you live in sees who you are as being inherently less than, many will try to “not” be that — albeit most likely on an unconscious basis.
If you live in a brutal and heartless world, learning how to also be brutal and heartless may seem like the only viable option to protect yourself.